U.S. patent number 5,732,303 [Application Number 08/850,868] was granted by the patent office on 1998-03-24 for detector using bar code for detecting the maximum/minimum diaphragm adjustment value of an exchange lens.
This patent grant is currently assigned to Samsung Aerospace Industries, Ltd.. Invention is credited to Jong-Sung Choi.
United States Patent |
5,732,303 |
Choi |
March 24, 1998 |
Detector using bar code for detecting the maximum/minimum diaphragm
adjustment value of an exchange lens
Abstract
A detector for detecting the maximum/minimum diaphragm
adjustment value of an exchange lens of a camera includes a bar
code, in which the maximum/minimum diaphragm adjustment value of an
exchange lens is printed in a binary code, formed on the lens and a
bar code reader on the camera for reading and decoding the bar
code. The bar code reader outputs an electric pulse signal
corresponding to the bar code by radiating a fixed scanning line at
the bar code.
Inventors: |
Choi; Jong-Sung (Kyungki-do,
KR) |
Assignee: |
Samsung Aerospace Industries,
Ltd. (Kyungsangnam-do, KR)
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Family
ID: |
19412212 |
Appl.
No.: |
08/850,868 |
Filed: |
May 2, 1997 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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630850 |
Apr 11, 1996 |
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Foreign Application Priority Data
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Apr 14, 1995 [KR] |
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95-8815 |
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Current U.S.
Class: |
396/532; 396/505;
396/529 |
Current CPC
Class: |
G03B
17/14 (20130101); G03B 7/20 (20130101); G03B
2206/00 (20130101); G03B 2217/18 (20130101) |
Current International
Class: |
G03B
7/20 (20060101); G03B 007/93 () |
Field of
Search: |
;354/286,289.1,289.11,289.12 ;396/505,529,530,532 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Malley; Daniel P.
Attorney, Agent or Firm: Finnegan, Henderson, Farabow,
Garrett & Dunner, L.L.P.
Parent Case Text
This application is a continuation of application Ser. No.
08/630,850, filed Apr. 11, 1996, now abandoned.
Claims
What is claimed is:
1. Apparatus for indicating the maximum/minimum diaphragm
adjustment value of a lens, comprising:
a lens, detachably mounted on a camera body, and including a
plurality of adjustment positions and a surface containing a bar
code indicating the maximum/minimum diaphragm adjustment value of
the lens, the bar code comprising a binary code having thick lines
and thin lines; and
a bar code reader, attached to the camera body, for outputting an
electric pulse signal corresponding to the bar code by radiating a
fixed scanning line to the bar code when the lens is mounted on the
camera, the bar code reader simultaneously outputting the
maximum/minimum diaphragm adjustment value indicated in the bar
code for all adjustment positions of the lens.
2. The apparatus of claim 1, wherein the bar code is expressed and
printed in Interleaved Two of Five (ITF) format.
3. The apparatus of claim 2, wherein the number corresponding to
the minimum diaphragm adjustment value is expressed as the first
two figures of the bar code and the number corresponding to the
maximum diaphragm adjustment value is expressed as the next two
figures of the bar code.
4. The apparatus of claim 1, wherein the bar code reader comprises
photoelectric elements.
5. A camera, comprising:
a camera body, including a lens mount;
a lens removably attached to said camera body, said lens having a
plurality of adjustment positions and including an engagement
portion for engaging the lens mount to attach said lens to the
camera, a base surface of the lens engagement portion including a
bar code, said bar code representing the maximum/minimum diaphragm
adjustment value of said lens in a binary code; and
a bar code reader disposed on the lens mount of said camera body in
position to read said bar code when said lens is attached to said
camera body and outputting a signal indicating the maximum/minimum
diaphragm adjustment value for said lens, the bar code reader
simultaneously outputting the maximum/minimum diaphragm adjustment
value indicated in the bar code for all adjustment positions of the
lens.
6. The camera of claim 5, wherein said bar code is expressed and
printed in Interleaved Two of Five (ITF) format.
7. The camera of claim 6, wherein the number corresponding to the
minimum diaphragm adjustment value is expressed as the first two
figures and a number corresponding to the maximum diaphragm
adjustment value is expressed as the next two figures of said bar
code.
8. The camera of claim 5, wherein said bar code reader includes
photoelectric elements.
9. The camera of claim 5, further comprising:
a diaphragm for receiving the signal from said bar code reader
indicating the maximum/minimum diaphragm adjustment value for said
lens, wherein a value of said diaphragm varies from the minimum
diaphragm adjustment value to the maximum diaphragm adjustment
value in accordance with the signal.
10. The apparatus of claim 1, wherein the camera includes a
diaphragm for receiving the electric pulse signal from said bar
code reader, and wherein a value of the diaphragm varies from the
minimum diaphragm adjustment value to the maximum diaphragm
adjustment value in accordance with the electric pulse signal.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to cameras that use an
exchange lens, and more particularly, to cameras having a detector
for detecting the maximum/minimum diaphragm adjustment value of an
exchange lens.
2. Discussion of the Related Art
Generally, a single-lens reflex camera may have multiple
performance modes, which use diaphragm area and shutter speed as
variables: (1) a manual mode where a user controls a diaphragm
adjustment value and shutter speed; (2) a diaphragm-priority mode
where the camera control unit automatically controls shutter speed
according to outside light after adjusting the diaphragm to a
definite value; (3) a shutter-priority mode where the camera
control unit automatically controls the diaphragm according to
outside light after adjusting the shutter speed to a definite
speed; and (4) an automatic mode where the camera control unit
controls the diaphragm value and shutter speed according to outside
light.
When selecting the shutter-priority mode and the automatic mode,
the camera control unit should perceive the maximum/minimum
diaphragm adjustment value of an attached lens so that the
diaphragm adjustment value may be controlled properly in the limit
area of the lens. The diaphragm adjustment value may vary according
to the type of lens.
An operating system in a conventional detector for detecting the
maximum/minimum diaphragm adjustment value of an exchange lens is
shown in FIG. 1. A camera 100 employing an exchange lens 102 is
composed of a diaphragm control ring 104 attached to the exchange
lens to control the opening and shutting quantity. The diaphragm
control ring includes projection parts 106, 108, which engage a
maximum diaphragm adjustment value perception shaft 110 on the
camera when the exchange lens is mounted on the camera.
When the exchange lens is attached to the camera, the projection
part 108 is in contact with a diaphragm adjustment value perception
shaft 112. Accordingly, if a user rotates the diaphragm control
ring 104 in the Z direction, the diaphragm adjustment value
perception shaft 112 is interlocked with part 22 and is rotated in
the Y direction. At this time, the diaphragm adjustment value
perception shaft 112 is located within the range between the
maximum diaphragm adjustment value and the minimum diaphragm
adjustment value of the lens.
The diaphragm adjustment value perception shaft 112 is electrically
connected to an interior rheostat (not shown) and inputs a signal
into the camera control unit corresponding to a variable resistance
value determined by the position shift of the shaft 112. The value
corresponding to the pattern position change of the position shift
of the shaft 112 relative to a fixed pattern is also inputted into
the control unit. Accordingly, if the position of a diaphragm
control ring 104 is fixed, the position of shaft 112 is set by
being interlocked with it. At this time, a diaphragm adjustment
value may be perceived as a consequence of the corresponding
signals input into the camera control unit.
When an exchange lens is joined to the camera at the stage in which
a diaphragm adjustment value control ring 104 is located at the
maximum diaphragm adjustment value, projection part 106 is in
contact with the maximum diaphragm adjustment value perception
shaft 110 and is rotated in the Y direction. When the lens is
joined to the camera at a stage other than the maximum diaphragm
adjustment value, the maximum diaphragm adjustment value perception
shaft 110 is rotated in the Y direction by a projection part 106,
if a user rotates a diaphragm control ring 104 toward the maximum
diaphragm adjustment value after joining the lens with the camera.
The maximum diaphragm adjustment shaft 110 and the projection part
106 are not joined at the range except the maximum diaphragm
adjustment value, are joined only at the maximum diaphragm
adjustment value, and perceive the maximum diaphragm adjustment
value.
The shaft 110 is electrically connected with a variable rheostat
and/or a fixed pattern in the same manner as the shaft 112, and
inputs an electrical signal into the camera control unit
corresponding to the position fixed according to the direction of
movement. The minimum diaphragm adjustment value may be interpreted
by reading the minimum diaphragm adjustment value corresponding
with the maximum diaphragm adjustment value.
Such a conventional detector is disadvantageous because the many
components used to connect the camera and lens and perceive the
maximum/minimum diaphragm adjustment value may generate loss, e.g.,
drawing and components work. Also, although various lenses have the
same maximum diaphragm adjustment value, there are many cases where
the minimum diaphragm adjustment values differ. Thus, errors in
reading the minimum diaphragm adjustment value of a lens according
to the perceived maximum diaphragm adjustment value are likely to
occur.
SUMMARY OF THE INVENTION
The present invention is directed to a detector that substantially
obviates one or more of the problems due to limitations and
disadvantages of the related art.
Additional features and advantages of the invention will be set
forth in the description which follows, and in part will be
apparent from the description, or may be learned by practice of the
invention. The objectives and other advantages of the invention
will be realized and attained by the apparatus particularly pointed
out in the written description and claims hereof, as well as the
appended drawings.
To achieve these and other advantages, and in accordance with the
purpose of the invention as embodied and broadly described, the
detector includes a bar code on the exchange lens, the bar code
representing the maximum/minimum diaphragm adjustment value of an
exchange lens in a binary code; and a bar code reader on the camera
and facing the bar code when the exchange lens is attached to the
camera, for reading the bar code and outputting a signal
corresponding to the bar code.
It is to be understood that both the foregoing general description
and the following detailed description are exemplary and
explanatory and are intended to provide further explanation of the
invention as claimed.
The accompanying drawings are included to provide a further
understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate an embodiment
of the invention, and, together with the description, serve to
explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating a conventional detector
for detecting the maximum/minimum diaphragm adjustment value of an
exchange lens.
FIG. 2 is a perspective view illustrating a detector for detecting
the maximum/minimum diaphragm adjustment value of an exchange lens
according to a preferred embodiment of the present invention.
FIG. 3 is a diagram illustrating an exemplary bar code for use with
the detector shown in FIG. 2.
FIGS. 4A to 4D are diagrams illustrating various types of bar codes
for use with the detector shown in FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to a preferred embodiment of
the invention, an example of which is illustrated in the
accompanying drawings. Wherever possible, the same reference
characters will be used throughout the drawings to refer to the
same or like parts.
A detector according to a preferred embodiment of the present
invention is illustrated in FIG. 2. An exchange lens 10 is
connectable to a camera 12 by engaging and mating a lens flange 14
with a corresponding groove 16 in camera. When joined, base 18 of
the lens abuts and faces base 20 of the camera.
The lens includes a diaphragm control ring 30 for adjusting the
diaphragm. The control ring includes a projection 32 that
interlocks with a position shaft 34 when the lens and camera are
joined, thus allowing the diaphragm position to be monitored by a
camera control unit.
The detector of the present invention includes a bar code 22
printed or otherwise formed on base 18. A bar code reader 24 is
similarly positioned on camera base 20 to read the bar code when
the camera and lens are joined. The bar code reader, which is
composed of photoelectric elements known in the art, outputs an
electric pulse signal corresponding to a perceived number by
radiating a scanning line to read the bar code 22.
Generally, a bar code denotes a number or a word expressed in a
binary code by a combination of thick and thin white or black
lines. By assigning a logical value 1, 0 to a thick or a thin white
or black line and printing the binary code as a serial signal, a
bar code reader can decode the bar code by radiating the bar code
at a uniform speed. The resultant electric signal is similar to
Morse code, and is decoded into a corresponding word or number by
being compounded.
Presently, at least four kinds of bar codes are commonly used. The
types of bar codes illustrated in FIGS. 4A to 4D may be described
according to the properties in Table 1.
TABLE 1 ______________________________________ Letter Ex- Mes-
Density Code pression sage letter/ Minimum FIG. name letter length
inch bar/mm Feature ______________________________________ 4A code
3 capital variable (H) 9.4 0.19 abundant of 9 numeral (M) 5.2 0.3
number of $/%+- (L) 0.53 0.53 letters for industry 4B NW7 numeral
variable (H) 10.0 0.17 for library, -$:/.+ (M) 5.0 0.33 medical
abcde (L) 3.3 0.53 institution, photo 4C Inter- numeral variable
(H) 18.0 0.19 possible leaved (M) 9.3 0.3 to raise the 2 of 5 (L)
5.3 0.53 letter density 4D UPC numeral fixed 1.26- common EAN 8
lines 0.33- goods code JAN 13 lines 0.66 throughout the world
______________________________________
The bar code illustrated in FIG. 3 is a code expressed in an
Interleaved Two of Five (ITF) format representing the number
"1236". As illustrated in FIG. 3, a white margin indicates a "start
machine" or start position. Two thin black lines express the
beginning of the bar code, and thick and thin black lines represent
the stop position.
TABLE 2 ______________________________________ Numeral Code Number
Code ______________________________________ 0 00110 5 10100 1 10001
6 01100 2 01001 7 00011 3 11000 8 10010 4 00101 9 01010
______________________________________
As shown in Table 2, a numeral is composed of five elements (5
lines) including two thick lines (a numeral always includes 2 thick
lines).
"1" in the number "1236" is expressed as "10001," as shown in Table
2. As illustrated in FIG. 3, a thick black line expresses "1", a
thin black line expresses "0", and the compounding of the two lines
expresses "10001." Then, the next number, "2", is expressed by
thick and thin white lines. As illustrated in FIG. 3, "01001" is
expressed by expressing a thick white line as "1" and a thin white
line as "0". The numbers "3" and "6" are expressed by the same
methods as "1" and "2", respectively, as illustrated in FIG. 3.
The maximum/minimum diaphragm adjustment value of a lens is
expressed with a bar code expression according to a preferred
embodiment of the present invention and is printed on the lens
base. In other words, the maximum/minimum diaphragm adjustment
value of an exchange lens is expressed as four figures, according
the ITF method. For example, if the minimum diaphragm adjustment
value of an exchange lens is "2.8" and the maximum diaphragm
adjustment value is "22", it is expressed as "2822" in the bar
code. If the minimum diaphragm adjustment value of an appropriate
exchange lens is "2" and the maximum diaphragm adjustment value of
one is "22", it is expressed as "0222" in the bar code.
The bar code reader 24 reads the value corresponding to the
maximum/minimum diaphragm adjustment value of a joined exchange
lens and outputs an electric signal. A camera control unit (not
shown) deciphers the maximum/minimum diaphragm adjustment value of
a joined exchange lens by compounding signals generated from the
bar code reader 24. Accordingly, the camera control unit of adjusts
the diaphragm adjustment value of an exchange lens according to the
deciphered maximum/minimum diaphragm adjustment value of an
exchange lens, when a shutter-priority mode or an automatic mode is
chosen.
As described above, the present invention provides a detector for
detecting the maximum/minimum diaphragm adjustment value of an
exchange lens by reading the diaphragm adjustment value, which is
expressed in bar code, with a bar code reader. The detector
simplifies construction and increases accuracy by eliminating
additional parts needed in conventional cameras for detecting a
diaphragm adjustment value.
It will be apparent to those skilled in the art that various
modifications and variations can be made in the disclosed product
without departing from the scope or spirit of the invention. Other
embodiments of the invention will be apparent to those skilled in
the art from consideration of the specification and practice of the
invention disclosed herein. It is intended that the specification
and examples be considered as exemplary only, with a true scope and
spirit of the invention being indicated by the following
claims.
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